28691860 has 12 divisors (see below), whose sum is σ = 60252948. Its totient is φ = 11476736.

The previous prime is 28691837. The next prime is 28691867. The reversal of 28691860 is 6819682.

It can be written as a sum of positive squares in 2 ways, for example, as 17589636 + 11102224 = 4194^2 + 3332^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28691867) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 717277 + ... + 717316.

It is an arithmetic number, because the mean of its divisors is an integer number (5021079).

Almost surely, 2^28691860 is an apocalyptic number.

28691860 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28691860 is an abundant number, since it is smaller than the sum of its proper divisors (31561088).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28691860 is a wasteful number, since it uses less digits than its factorization.

28691860 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1434602 (or 1434600 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 40.

The square root of 28691860 is about 5356.4783206879. The cubic root of 28691860 is about 306.1396403691.

The spelling of 28691860 in words is "twenty-eight million, six hundred ninety-one thousand, eight hundred sixty".